Summary Of Significant Accounting Policies (Schedule Of Accumulated Other Comprehensive Loss) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014		Sep. 30, 2013
(Increase) Decrease In Accumulated Other Comprehensive (Income) Loss [Roll Forward]
Beginning balance			$ 4,202		$ 24,743
Change excluding amounts reclassified from accumulated other comprehensive loss			(338)		(6,804)
Amounts reclassified from accumulated other comprehensive loss			(1,486)		(2,792)
Net other comprehensive income	(534)	(517)	(1,824)		(9,596)
Ending balance	2,378	15,147	2,378		15,147
(Gain) Loss On Investments [Member]
(Increase) Decrease In Accumulated Other Comprehensive (Income) Loss [Roll Forward]
Beginning balance			(340)		0
Change excluding amounts reclassified from accumulated other comprehensive loss			(203)		34
Amounts reclassified from accumulated other comprehensive loss			38	[1]
Net other comprehensive income			(165)		34
Ending balance	(505)	34	(505)		34
(Gain) Loss On Cash Flow Hedges [Member]
(Increase) Decrease In Accumulated Other Comprehensive (Income) Loss [Roll Forward]
Beginning balance			(1,233)		7,489
Change excluding amounts reclassified from accumulated other comprehensive loss			(135)		(6,735)
Amounts reclassified from accumulated other comprehensive loss			(1,280)	[2]	(1,802)	[2]
Net other comprehensive income			(1,415)		(8,537)
Ending balance	(2,648)	(1,048)	(2,648)		(1,048)
Defined Benefit Pension Plan [Member]
(Increase) Decrease In Accumulated Other Comprehensive (Income) Loss [Roll Forward]
Beginning balance			5,775		17,254
Change excluding amounts reclassified from accumulated other comprehensive loss			0		(103)
Amounts reclassified from accumulated other comprehensive loss			(244)	[3]	(990)	[3]
Net other comprehensive income			(244)		(1,093)
Ending balance	$ 5,531	$ 16,161	$ 5,531		$ 16,161

[1] This reclassification component is included in interest and other income.

[2] This reclassification component is included in interest expense (see Note 7 for additional information).

[3] This reclassification component is included in the computation of net periodic benefit cost (see Note 13 for additional information).